1. Field of the Invention
The present invention relates to the field of handphones and, more particularly, to a handphone capable of inputting characters like a computer keyboard by installing a keypad on the phone body and also installing an extra keypad on the phone cover.
The present application is based on Korean Application Nos. 2002-3857, filed Jan. 23, 2002, and 2002-47896, filed Aug. 13, 2002, and both of which are incorporated herein by reference.
2. Description of the Related Art
Various handphone terminals (hereinafter, referred to as handphones) using a radio communications network are being introduced with the development of information communications. Handphones are being rapidly used thanks to the convenience of its use that users can make calls freely regardless of the location. A wireless Internet service, a combination of a handphone and an Internet service, is recently being used. In addition, a short message service (SMS) or an e-mail service is carried out through handphones.
As for handphones, an increase in the importance of the character input function leads to an increase in the size of a liquid crystal display (LCD). In the early stage, LCD devices only could display 2 to 3 lines with the 7-segment system, while more recently used LCD devices can display 5 lines with the dot matrix system.
However, an input mechanism for inputting character messages to a handphone has not caught up with the rapidly increasing demand and use of character information transmission.
Handphones have a significant difficulty in sending and receiving a sufficient amount of character information, because of the restriction that handphones should be kept light and small. That is, as handphones should be small enough to fit easily into the palm of a hand, their keypads can only have a basic structure in which the size of the keyboard or the number of keys is limited, so that only the minimum amount of information can be input. That is, current handphones have a normal telephone keypad composed of 10 numeric keys and 5 function keys.
As the search and input of information requested by users are considerably limited, a method for rapid, accurate character input is needed in order to actively use a wireless Internet service using handphones.
There are proposed various types of wire and wireless keyboards that enable users to easily input a desired message by connecting the keyboard to a handphone as needed while carrying. However, these keyboards are to be carried in addition to a handphone and to be coupled to a handphone to be used.